Shelving unit



FIG. 1 is a front perspective view of a shelving unit showing my new design;

FIG. 2 is a front elevational view;

FIG. 3 is a rear elevational view;

FIG. 4 is a top plan view;

FIG. 5 is a right side view; and,

FIG. 6 is a left side view. 

The ornamental design for a shelving unit, as shown and described. 